cardiac catheterization

Image credit: Stanford Hospital &
Clinics.

Cardiac catheterization is a minimally invasive medical procedure used to diagnose and treat certain heart conditions. A long, thin, flexible tube
called a catheter is introduced into a blood vessel in the arm, upper thigh
(groin), or neck and threaded up into the heart. Through the catheter, a
doctor can perform diagnostic tests and treatments on the heart. Cardiac
catheterization is usually performed in a hospital by cardiologists, who
specialize in the treatment of heart diseases.

To diagnose some heart conditions, a special dye, known as a contrast
medium, may be put into the catheter to make the inside of the heart
and blood vessels show up on X-rays.
Samples of blood and heart muscle may
be taken through the tube. Certain heart problems can be treated during
this procedure.

Why is cardiac catheterization done?

Often a cardiac catheterization is performed to find out why a patient is
having chest pain. The procedure can reveal blocked or narrowed places in
the heart's arteries that can cause this
pain. During cardiac catheterization, it may be possible to open up the
blocked arteries by doing another procedure called angioplasty.

Most people who have heart attacks have arteries that are partly or completely blocked. That is why cardiac
catheterizations are often carried out after patients have heart attacks.
The procedure can indicate if there are blocked arteries that can be treated
with angioplasty or surgery.

Another reason for doing cardiac catheterizations is to look at the overall
shape of the heart and its four chambers (the atria and ventricles). This makes it possible
to:

Find any likely problems in people about to have open heart surgery

See heart abnormalities in children or adults

Sometimes cardiac catheterization is performed to see how well the valves (flaps of tissue) at the openings and exits of the heart chambers are working.
To do this, measurements are made of the blood flow and oxygen levels in
different parts of the heart. Cardiac catheterization is also done to check
the functioning of artificial heart valves and to carry out minor surgical
procedures on the heart. These minor procedures may include the removal
(biopsy) of a small piece of heart tissue
to see if there is an infection or tumor, or the repair of holes in the
heart or other heart defects.

What are the risks for
cardiac catheterization?

Cardiac catheterization is a common medical procedure that rarely causes
serious problems. But complications can include:

How to prepare for a cardiac catheterization

Before having a cardiac catheterization, it is a good idea for the patient
to meet with his/her doctor to learn about the procedure and how to prepare
for it. In that meeting, the patient might discuss things such as:

Any medicines he/she is taking, and whether he/she should stop taking
some of these drugs before the procedure

Whether he/she has diabetes, kidney disease, or other conditions that
may require taking extra steps during or after the procedure to avoid
complications

Patients are not usually allowed to drive the same day they have a cardiac
catheterization. If they don't have to stay overnight after this procedure,
they should arrange for a ride to and from the hospital.

What happens during a cardiac catheterization?

During a cardiac catheterization, the patient is kept on his/her back and
awake. That way the patient can follow instructions given during the procedure.
A drug is administered to aid relaxation, which make make the patient sleepy.

A doctor or nurse will numb the area where the small plastic tube (catheter)
will enter the blood vessel through a small cut or needle in the arm, upper
thigh (groin), or neck. The catheter is then threaded through the vessel
and into the chambers of the heart. Special X-ray movies are taken of the
tube as it is threaded up into the heart. This helps the doctor see where
to put the tube.

Once the catheter is at the right spot, it can be used it to conduct several
tests or treatments. Often, special dye is put in the tube to make the inside
of the heart's arteries and other structures show up on an X-ray. A procedure
called angioplasty may be used to open up the blocked arteries and blood
samples may be taken from different parts of the heart or do minor heart
surgery.

Once the doctor does all of the needed tests or treatments, the catheter
will be taken out. The opening in the blood vessel that the tube went through
will then be closed up and bandaged. A small sandbag or other type of weight
may be put on top of the bandage to apply more pressure. This will help
prevent major bleeding from the site.

What happens after
a cardiac catheterization?

After a cardiac catheterization, the patient will be moved to a special
care area where you will stay for several hours or overnight. While recovering
in this area, the patient's movement is limited to avoid bleeding from where
the tube (catheter) was inserted. Nurses will check your heart
rate and blood pressure regularly.
They will also check to see if there is any bleeding from the tube insertion
site.

Eventually, a small bruise will appear where the tube was put in. That area
may feel sore or tender for about a week. The patient should let his/her
doctor know if:

There is a constant or large amount of blood at the site that can't
be stopped with a small bandage.

There is any unusual pain, swelling, redness, or other signs of infection
at or near the insertion site.

The patient may be asked to avoid certain activities, such as heavy lifting,
for a short time after the procedure.